Introduction: Revision arthroplasty using the impaction grafting technique is an increasingly popular technique. The lost bone stock is replaced rather than substituted with ever increasing amounts of metal. There have been many advances in the understanding of this technique in recent years. It has recently been shown that washing of the graft improves the biomechanical strength, bony ingrowth and biocompatibility of morsellised allograft bone. The aim of this study was to identify the most efficacious method of washing morsellised allograft in the operating room.

Methods: Fresh frozen femoral heads identified for research purposes were randomly divided into four groups. Group A was washed using a serial dilution technique at 37°C, group B serial dilution at 60 °C, group C pulsed lavage wash at 37°C and group D pulsed lavage wash at 60 °C. Three-gram samples of each femoral head were taken prior to washing. The heads were then washed according to the grouping. The unwashed and washed morsellised bone was then assessed for the presence of protein, haemoglobin, DNA and lipid using spectrophotometric analysis techniques. The removal of these marrow components from the femoral heads in each group was assessed as a proportion of the original content.

Results: All washing techniques removed a large proportion of the marrow load of the femoral heads. The most efficacious technique was washing by serial dilution (removal rate 67.5–87.4%). Washing by pulsed lavage removed less marrow (28.4–80.9%). Protein showed the highest removal rate (80.9–86.4%) and haemoglobin the lowest (28.4–67.5%). Removal of lipid was most affected by temperature with a larger proportion removed at 60°C as compared to 37°C.

Conclusion: We conclude that the most efficient method of washing morsellised allograft bone for impaction grafting is by serial dilution with fluid at 60°C. This information should improve the results of impaction grafting, as it is known that cleaner bone results in improved biomechanical stability, enhanced biological compatibility and accelerated bony ingrowth.

Study Design: A prospective observational study of scoliosis patients who were on non-invasive night ventilation for respiratory failure.

Objective: To report the results of spinal deformity correction in a group of patients with progressive scoliosis and rare forms of muscular dystrophy/myopathy with respiratory failure who were on nocturnal ventilatory support at the time of surgery.

Subjects: 9 patients (6 males, 3 females) with scoliosis and respiratory failure. The mean age at surgery was 12.4years (range 8–16yrs). There were 4 patients with multicore myopathy, 2 with merocin negative congenital muscular dystrophy, 1 with Ullrichs muscular dystrophy, 1 patient with congenital AcylCOA dehyrogenase deficiency and 1 with congenital scoliosis and dextrocardia. All the patients had overnight pulse oximetry, which showed episodes of desaturation at night. This was reversed with the onset of nocturnal ventilation. All the patients underwent posterior fusion performed by the same surgeon. Mean follow-up was 40 months (range 10 to 75)

Outcome Measures: Lung function, Cobb angle, Length of ICU stay, complications

Results: Mean vital capacity at time of surgery was 20% (range 13–28%). All patients recovered well following surgery with no cardiac or pulmonary complications. The mean stay in the ICU was 2.7 days (range 2–5). The mean hospital stay was 14.2 days (range 10–21). The mean preoperative Cobb angle was 70.2 degrees (range 55–85). The average change in the Cobb angle post-operatively was 32 degrees (range 16–65 degrees). The mean vital capacity of patients at latest follow up was 18% (range 10–32%). There was no loss of correction at latest follow-up. None of these patients lost their ambulatory capacity following surgery.

Conclusion: This is the first study reporting results of deformity correction in patients on ventilatory support. Spinal deformity correction in patients on non-invasive nocturnal ventilation presented no increased risk of complications.

Objective: To assess the effect of spinal surgery and nocturnal ventilation on lung function and survival in patients with scoliosis secondary to Duchenne Muscular Dystrophy.

Study design: Prospective, observational study by a single observer (Research Physiotherapist).

Subjects: 80 patients with Duchenne Muscular Dystrophy were treated between 1986 and 2002. During this period 40 patients underwent a spinal fusion at a mean age of 14.05y (95 % CI 13.6 – 14.6). Nocturnal ventilation was commenced when symptoms and signs of respiratory failure were evident. The mean FVC at commencement of nocturnal ventilation was 0.41 litres. The patients were divided into 2 groups based on whether they received nocturnal ventilation. A total of twenty eight patients received nocturnal ventilation and 52 did not. The groups were further sub-divided based on whether they had spinal fusion. There were fourteen patients in each sub-group of the ventilated group and 26 patients in each sub-group of those that were not ventilated.

Outcomes: Serial forced vital capacity (FVC) measurements and survival measured by Kaplan Meir survival analysis.

Results: The mean vital capacity dropped from 1.41 l (95 % CI 1.21 – 1.61) to 1.13 (95 % CI 0.893 – 1.37), a year post-operatively. This was not associated with the development of respiratory compromise. The vital capacity improved gradually, reaching the pre-operative level before it declined again. The shortest survival was seen in patients who received neither surgery nor ventilation (median survival 19.7y). The patients who received surgery but no ventilatory support were not as good as the patients that were ventilated but did not have surgery (median survival 24.3y). The best results were seen in the patients who had both surgery and ventilation (median survival 26.4y). The worst prognosis is in patients with early onset symptomatic cardiomyopathy (6 patients, with a median survival of 16.3y).

Conclusion: Nocturnal ventilation is the most important factor in the improvement in survival of patients with Duchennes muscular dystrophy. Spinal surgery is also beneficial and the best results are in those patients who have both.